Repeating circuit interrupter



Dem 1965 E. J. STRAMOWSKI 3,225,161

REPEATING CIRCUIT INTERRUPTER Filed June 5, 1963 5 Sheets-Sheet 1 'IIII/IIIIIIIIIIIIIIIIIIIIIIIII" INVENTOR.

farm/22d J .Stramowsm' Dec. 21, 1965 E. J. STRAMOWSKI REPEATING CIRCUIT INTERRUPTER 5 Sheets-Sheet 2 Filed June 5, 1963 IN VENTOR.

fdmmd J Stramowsxz' vitwrng E. J. STRAMOWSKI 3,225,161

REPEATING CIRCUIT INTERRUPTER Dec. 21, 1965 5 Sheets-Sheet 3 Filed June 5, 1963 Edmund J tmmazz/s/d Dec. 21, 1965 E. J. STRAMOWSKI REPEATING CIRCUIT INTERRUPTER 5 Sheets-Sheet 4 Filed June 5, 1963 INVENTOR. Edmond J Stramowsm' fidtormy Dec. 1965 E. J. STRAMOWSKI REPEATING CIRCUIT INTERRUPTER 5 Sheets-Sheet 5 Filed June 5, 1963 m 2 W m0 W Em W V d Z mw fi 5 Q WM mm i United States Patent 3,225,161 REPEATING CIRCUIT INTERRUPTER Edmund J. Stramowski, University City, Mo., assignor to McGraw-Edison Company, Milwaukee, Wis, a corporation of Delaware Filed June 5, 1963, Ser. No. 285,761 11 Claims. (Cl. 20092) This invention relates to repeating circuit interrupters and more particularly to a motor operated actuating mechanism for a repeating circuit interrupter.

It is an object of the invention to provide a new and improved motor operated actuating mechanism for repeating circuit interrupters.

Another object of the invention is to provide a motor actuated operating mechanism for repeating circuit interrupters wherein opening energy is available whenever the circuit breakers interrupting contacts are closed.

A further object of the invention is to provide a circuit breaker operating mechanism having spring operated opening and reclosing means wherein energy is stored in the switch opening spring whenever the main contacts are closed.

Yet another object of the invention is to provide a ci'rcuit breaker operating mechanism wherein a motor extended closing spring provides stored energy for closing and latching the circuit breakers main contacts and for charging opening spring means regardless of the availability of energy from the system being protected.

A still further object of the invention is to provide a circuit breaker operating mechanism having a motor charged closing spring wherein the motor is coupled to the closing spring through an involuted cam so that the motor load remains constant even though the spring force increases as it is being charged.

These and other objects and advantages of the instant invention will become more apparent from the detailed description thereof taken with the accompanying drawings in which:

FIG. 1 is a side elevational view, with parts broken away, of a circuit breaker incorporating the instant invention;

FIG. 2 is a front elevational view of the circuit breaker operating mechanism;

FIG. 3 is a side elevational view, partly in section, of a portion of the switch operating mechanism illustrated in FIG. 2;

FIG. 4 is a view taken along line 4-4 of FIG. 5;

FIG. 5 is a view taken along lines 55 of FIG. 4;

FIGS. 6, 7 and 8 schematically illustrate the operation of the switch operating mechanism according to the instant invention; and

FIG. 9 schematically illustrates the motor control circuit of the mechanism shown in FIGS. 2-8.

Referring now to the drawings in greater detail, FIG. 1 shows a polyphase repeating circuit interrupter designated generally by the reference numeral 10 and having a tank 12 provided with a cover 13 which supports porcelain terminal bushings 14 for connection to line wire, not shown. The bushings 14 extend interiorly of tank 12 and beneath the surface of a suitable dielectric fluid 15, such as oil, which substantially fills the tank 12. The stationary portions of the contact structure 17 are each disposed in a suitable arc interrupting assembly 18 both of which are suspended from their associated bushings 14.

An operating shaft 22 extends lengthwise of the tank 12 and beneath the cover 13 and has a plurality of crank arms 23 affixed thereto and extending transversely therefrom for pivotally engaging the upper ends of insulating links 25 each of which extends downwardly through the interrupting assembly 18 of each phase to engage a bridging bar 26 which carries the movable portion of contacts 17 so that the contacts 17 in each phase may be simultaneously opened.

An actuating mechanism 30 according to the instant invention is disposed in a metallic housing 31 suitably affixed adjacent one end of the tank 12. The operating shaft 22 is shown in FIG. 1 to extend through the end of the tank cover 13 and into the housing 31 for actuation by the operating mechanism 30. A control mechanism for initiating the various opening and closing operations of the circuit interrupter 10, as will be described morefully hereinbelow, is disposed within a separate metallic housing 32 aifixed to one side of the housing 31 and is electrically connected to the actuating mechanism 30 by a cable 34. As will be understood by those skilled in the art, many types of control mechanisms suitable for use with the circuit breaker 10 are well known in the art and accordingly, the mechanism 32 will not be discussed in detail. For a more complete description of a circuit breaker control mechanism capable of use with the disclosed circuit breaker, reference is made to copending application Serial No. 136,352, filed September 6, 1961, and assigned to the assignee of the instant invention.

Referring now to FIGS. 2 and 3, the operating mechanism 30 is shown to include a latch assembly for holding the operating shaft 22 in a switch closed position against the influence of an opening spring 41. A trip solenoid 42 is provided for tripping the latch assembly 40 so that the operating shaft 22 is freed for rotation by spring 41 to a switch open position. After a switch opening operation springs 44 provide energy for simultaneously rotating the operating shaft 22 in a switch closing direction, for resetting the latch mechanism 40 and for extending the opening spring 41. The energy for extending the springs 44 is provided by a motor 46 which is coupled to the opening springs 44 through a gear reduction mechanism 48 and a cam member 49. A brake 47 is also coupled to the motor 46 for arresting its operation when required. The operating mechanism 30 is supported on an inverted U-shaped frame member 50 rigidly secured to the back wall 52 of the metallic housing 31.

The latch mechanism 40 is shown to be mounted between a pair of parallel plates 54 which extend integrally upward from a base plate 55 suitably affixed to the upper surface of the frame member 50. The plates 54 serve to support the latch mechanism 40 and to provide bearings for the various rotatable shafts thereof.

Referring now specifically to FIGS. 4 and 5, it can be seen that one end of the opening spring 41 is anchored at 57 to the back wall 52 of the housing 31 and its other end is connected to the free end of an arm 58 which is rigidly affixed to the operating shaft 22. The opening spring 41, which is shown in its extended condition in FIG. 4, tends to contract thereby rotating the operating shaft 22 counterclockwise to move the insulating links 25 downwardly and thereby open the circuit breakers contacts 17. This is prevented, however, by the latch assembly 41 which is shown in FIG. 4 to be in its latched or rigid condition.

The latch assembly 40 includes a collapsible linkage 5 9 having a first pair of parallel toggle links 60 which are pivotally connected at 61 :to the free end of an arm 63 rigidly afiixed to the operating shaft 22 and a second pair of parallel toggle links 64 pivotally connected by a knee pin 66 to the other end of the link-s 60. The collapsible linkage 59 also includes a generally U-shaped member 68 which is rotatably mounted at one end on a shaft 70 extending between the plates 54 and which has a pair of arms which are pivotally connected by a pin 71 to the other ends of the second pair of toggle links 64. Also rotatably mounted around the pins 66 and 71 and disposed between the parallel links 60 and 64 are rollers 73 and 74, respectively.

The opening spring 41 tends to collapse the linkage 59 so that the roller 73 moves generally downward and to the left as viewed in FIG. 4 and the roller 74 tends to move upward and to the left. When the assembly 40 is in its latched condition such movement of roller 73 is prevented by a latch prop member 76 which is rotatably mounted on a shaft 77 and which has a latch arm 79 for engaging the roller 73. The prop latch 7-6 is urged toward counterclockwise rotation and into its latched position shown in FIG. 4 by a torsion spring 80 which acts to hold an ear '81 in engagement with a stop pin 83 extending between the plates 54.

Movement of the roller 74 is prevented when the latch assembly 40 is in its rigid condition by a latch lever 86 pivotally mounted on a shaft 88 and having a first latch arm 89 which is urged into engagement with the roller 74 by a torsion spring 91 which normally holds the latch lever 86 in engagement with a stop pin 92 extending from one of the plates 54.

It will be appreciated that the force of the opening spring 41 acting through the collapsible linkage 59 would normally be sufficient to overcome the torsion spring 91 and rotate the latch lever 86 counterclockwise as viewed in FIG. 4 but this is normally prevented by a half shaft latch 94 rotatably mounted between the plates 54 and whose cylindrical surface 96 is engaged by a roller 97 carried on the bifurcated end of a second latch arm 99 on the latch lever 86.

With reference .to FIGS. 2 and 5, the half shaft latch is shown to extend beyond one of the plates 54 and to carry a trip lever 100 at its outer end. A spring 192 which engages one end of the trip lever 11M) urges the lever 100 clockwise against a stop pin 1113 to thereby hold the shaft 94 in its latched position. A trip pin 105 extends laterally from the other end of the lever 100 for engagement by the plunger 106 of the trip solenoid 42. As will be discussed more fully hereinbelow, energization of the trip solenoid 42 will rotate the lever 100 counterclockwise and thereby initiate a switch opening operation.

The closing springs 44 are shown in FIG. 2 to be connected at their upper end to the frame member 50 and at their lower ends to a yoke 110. A closing rod 112 is connected at its lower end to the yoke 1 between the closing springs 44 and extends upwardly therefrom through a bushing 113 in the frame member 50 and the base 55 of the latch mechanism 46 at a point between the plates 54 and below the roller 73. The closing rod 112 also passes through a bushing 117 rigidly affixed to the rear wall 52 of the housing 3 1 to provide additional guidance.

The motor 46 is mounted on a frame 120 which is secured to the frame member 50 and to the back wall 52 of the housing 31. The frame 120 also supports the cam 49 and the gear reduction mechanism 48 between the closing rod 112 of the back wall 52: As seen in FIG. 3, the gear reduction mechanism 48 includes an input shaft 122 coupled to the motor 46 and an output shaft 128 which carries the cam 49.

The operating mechanism is shown in FIG. *2 to be in its latched position with both the opening spring 41 and the closing springs 44 in an extended position. When the mechanism is in this condition, the closing springs tend to move the closing rod 112 upwardly but this is prevented by the engagement of a follower 132 carried by the closing .rod V112 and the surface of the cam 49.

FIG. 6 schematically illustrates the operating mechanism when the contacts 17 are in their closed position. Should a trip signal be received by the solenoid 42 its plunger 106 will rotate the latch lever 101], and hence, the latch shaft 94 counterclockwise so that the roller 97 is moved off of the arcuate portion 96 thereof and onto the planar surface 98. The latch lever is thereby freed for counterclockwise rotation to permit the opening spring 41 to collapse the linkage 59 and rotate the operating shaft 22 counterclockwise so that the main contacts 17 are opened. This places the operating mechanism in its position shown in FIG. 7.

It can be seen from FIG. 4 that when the linkage 59 is rigid, the opening spring 41 acts in a direction substantially parallel to the links 60 and 64. Thus, the initial action of the linkage 59 after the latch lever 86 has been released, is for roller 74 to force lever 86 counterclockwise against spring 91. Upon this event, the opening spring 41 is free to rotate the operating shaft 22 counterclockwise as the links 60 and 64 are transposed toward the left without breaking toggle and the member 68 is pivoted counterclockwise against the action of spring 69 to its position shown by phantom lines in FIG. 7. When the main contacts reach their fully open position, movement of the links 61 and 64 toward the left as seen in FIG. 7 ceases whereupon spring 69 rotates member 6 8 clockwise to its original position as the links 60 and 64 break toggle and roller 73 moves downwardly. This re-engages the roller 74 and the latch arm 89, the latter of which has been returned to its original position by spring 69. It can be seen, therefore, that because the opening spring 41 acts at a small angle relative to toggle links 60 and 64, a larger proportion of the spring force is available for opening the main contacts and collapsing the linkage 59.

As the contacts 17 reach their fully opened position the motor 46 is energized to begin rotating the cam 49 counterclockwise as viewed in FIGURE 7. After a short interval the cam 49 has rotated to the point where its cam surface 49a has moved out of engagement with the roller 132 whereupon the latter is adjacent the flattened portion 49b of said cam. This frees the closing springs 44 for contraction which moves the contact rod 112 upwardly where its upper end impacts the roller 73 to straighten the toggle links 61 and 64 to thereby rotate the operating shaft 22 clockwise into a switch closed position and to extend the opening spring 41. Also, the roller 73 is moved onto the prop latch 76 to latch the collapsible linkage 59 since the roller 74 and the latch lever 86 have already returned to their latched positions. The operating mechanism 31 is thereby placed in its condition in FIGURE 8.

If a trip signal is received during a closing operation, the latch shaft 94 will rotate to release the latch lever 86 so that the linkage member 68 can rotate counterclockwise so that the roller 73 is permitted to roll off of the closing rod 112 and the contacts 17 are not closed. Thus the mechanism is trip free. It can also be seen that when the operating mechanism is in its position shown in FIGURE 8 the opening spring 41 is fully extended so that if another trip signal is received it can immediately open the main contacts 26 even though the motor 46 has not completed cycling.

After the closing rod 112 has reset the collapsible linkage 59 and extended the opening spring 41 the motor 46 continues rotating to move the cam surface 49a into engagement with the follower 132 on the closing rod 112 thereby forcing the rod downwardly as viewed in FIG- URE '8 to extend the closing springs 44. Such movement continues until the closing springs 44 are fully extended whereupon a limit switch is actuated to open the motor circuit. This returns the operating mechanism 36 to its latch close position shown in FIGURE 6.

The surface 49a of the cam 49 is shown in FIGURE 2 to be an involute wherein its slope is constantly decreasing. This serves to maintain the motor load uniform as the closing springs 44 are extended and their reacting force increases. Thus as the spring force increases the angle of the inclined surface presented to the follower 132 decreases proportionally so that the motor load remains constant.

FIGURE 9 shows the trip coil and motor control circuits for the operating mechanism 31). Here the coil of the trip solenoid 42 is shown connected to a DC. source 141 through a first pair of normally open contacts M3 which are operated by the control 32 in the manner discussed in the aforementioned application. Also in series with trip solenoid 42 is a second pair of contacts of a clapper switch 144 which is shown in FIGURE 2 to have a clapper arm 145 engaged by the crank arm 58 mounted on the operating shaft 22 when the main contacts 17 are in their closed position. When the clapper arm 14 5 is engaged as shown in FIGURE 2, the contacts of the clapper switch 144 are closed.

From the description thus far it will be evident that when the control 32 senses an abnormal condition in the circuit being protected and closes contacts 143, the trip solenoid 42 will be energized to initiate a switch opening operation in the manner described hereinabove which also releases the clapper arm 145 to open contacts of the clapper switch 144 and de-energize the trip solenoid 42.

The motor 46 and the brake 47 are shown in FIGURE 8 to be connected in parallel to each other and to an alternating current cource 146 through the normally open contacts 148a of the relay 148 and the contacts 151111 of a holding switch 150. With reference to FIGURE 2, the relay 148 is shown mounted on the frame member 513 above the motor 46 and the switch 150 is shown mounted below the frame 50 and adjacent the closing rod 112. The closing rod 112 has a recess 151 on its surface adjacent the switch 150 and which is engageable by a roller arm 153 on said switch. When the closing rod 112 is in its fully extended position shown in FIGURE 2 the roller arm 153 engages the elevated surface of said rod wherein the contacts 150a are open. The length of the recess portion 151 of rod 112 relative to the total stroke thereof, taking into account the fact that the motor is not stopped abruptly but slows down, is such that when the rod is in its fully contracted position the roller arm 153 will also be on the elevated surface of said rod so that contacts 150a will be open. However, when the closing rod 112 is in an intermediate position during motor operation, the roller arm 153 will be in the recess 151 whereupon contacts 150a. will be closed.

The relay 148 is shown in FIGURE 9 to be connected across the DC. source 141 through normally open contacts 155 which are operable by the control mechanism 32, the normally open contacts 156a of a switch 156 mounted adjacent the operating shaft 22, and the normally closed contacts of a manual switch 158 whose purpose will be described more fully hereinbelow. Switch 156 is shown connected by a link 159 to the crank arm 58 so that when the main contacts 17 are in their open position, contacts 1561; will be closed and when main contacts 17 are closed contacts 156a will be open.

It can thus be seen that when the main contacts are in their tripped open position and the control 32 closes the contacts 155 to initiate a switch closing operation, relay 148 will be energized to close the contacts 143a and thereby energize the motor 46 and release the brake 47. As the motor begins operating and the closing rod 112 begins moving downwardly the roller arm 153 of switch 151) will move onto the recess portion 151 closing contacts 15110. As a result, the motor 46 and the brake 47 remain energized after the relay 148 is de-energized by the opening of contacts 155 and 156a.

In order to manually trip the circuit breaker a manual trip lever 16% is pivotally mounted at 161 on one of the plates 54 adjacent the trip lever 100 for pivotal movement into engagement with the trip pin 105 to initiate a switch opening operation but this is normally prevented by a spring 162. The manual trip lever 160 is rotated by pushing upwardly on a push rod 164 that extends downwardly through the frame 51) to an accessible point within the cabinet 31. Rotation of the manual trip lever 16%) also engages a clapper 163 on switch 158 which opens to prevent energization of the relay 148 so that the motor will not be energized to initiate a closing operation until the plunger 164 is released.

While only a single embodiment of the invention has been illustrated and described it is not intended to be limited thereby but only by the scope of the appended claims.

I claim:

1. A circuit breaker having main switch means, opening spring means coupled to said main switch means for moving the same to an open position, releasable means having a held position for holding said opening spring in a charged condition and said main switch means closed, trip means for said releasable means and operable to initiate a switch opening operation, switch closing means movable into engagement with said releasable means for moving the latter to its switch held position, closing spring means urging said switch closing means toward engagement with said releasable means, motor means for normally holding said switch closing means away from said releasable means and said closing spring means in a charged condition, said motor means being operative to elease said switch closing means for movement by said closing spring means into engagement with said releasable means to place the same in its held position to close said main switch means and to charge said opening spring means, said motor means also being operable after a switch closing operation to move said switch closing means out of engagement with said releasable means wherein said closing spring means are charged.

2. A circuit breaker having main switch means, opening spring means coupled to said main switch means for moving the same to an open position, linkage means coupled to said opening spring means, latch means for holding said linkage means in a switch closed position and to maintain said opening spring means in a charged condition, latch release means, a switch closing member movable into engagement with said linkage means for moving the latter to its switch closed position, closing spring means urging said closing member toward engagement with said linkage means, motor means for normally holding said closing member away from said linkage means and said closing spring means in a charged condition, said motor means being operable to release said closing member for movement by said closing spring means into engagement with said linkage means to close said main switch means and to charge said opening spring means, said motor means also being operable after a switch closing operation to move said closing member out of engagement with said linkage means wherein said closing spring means is charged.

3. A circuit breaker having main switch means, opening spring means coupled to said main switch means for moving the same to an open position, collapsible linkage means coupled to said opening spring means, latch means for holding said collapsible linkage means in a rigid condition and to maintain said opening spring means charged and said main switch means closed, latch release means, a switch closing member movable into engagement with said linkage means for placing the latter in its rigid condition, closing spring means urging said closing member toward engagement with said linkage means, operating means for normally holding said closing member away from said linkage means and said closing spring means in a charged condition, motor means for releasing said closing member for movement by said closing spring means into engagement with said collapsible linkage means to close said main switch means and to charge said opening spring means, said motor means also being operable after a switch closing operation to move said closing member out of engagement with said linkage means and into a held position relative to said operating means wherein said closing spring means is charged.

4. A circuit breaker having main switch means, opening spring means coupled to said main switch means for moving the same to an open position, collapsible linkage means coupled to said opening spring means, latch means for holding said collapsible linkage means in a rigid condition to maintain said opening spring means charged and said main switch means closed, latch release means, a switch closing member movable into engagement with said linkage means for placing the latter in its rigid condition, closing spring means urging said switch closing member toward engagement wtih said linkage means, cam means having a first position for normally holding said switch closing member away from said linkage means and said closing spring means in a charged condition and a second position wherein said switch closing member is released for movement by said closing spring means into engagement with said collapsible linkage means to place the same in its rigid latched position, motor means operable after a switch opening operation to move said cam means from its first to its second position to close said main switch means and to charge said opening spring means, said motor means also being operable after a switch' closing operation to rotate said cam means to its first position to move said closing member away from said linkage means wherein said closing spring means is charged.

5. A circuit breaker having main switch means, opening spring means coupled to said main switch means for moving the same to an open position, linkage means coupled to said opening spring means, latch means for holding said linkage means in a switch closed position to maintain said opening spring means extended, latch re lease means, a switch closing member movable into en gagement with said linkage to move the latter to its switch closed position, closing spring means urging said closing member toward engagement with said linkage means, cam means rotatably mounted adjacent said switch closing member and having an involuted surface, a follower member secured to said closing member and being engageable with said surface, said cam surface having a first portion displaced from the axis of rotation for holding said closing member away from said linkage means and said closing spring means in an extended condition and a second portion proximate to said axis which per mits said closing member to engage said linkage means, motor means for rotating said cam means to move its second portion into engagement with said follower to initiate a switch closing operation andto extend said opening spring, said motor also being operable after a switch closing operation to move the first portion of said surface into engagement with said follower to move the closing member away from said linkage means and to extend said closing spring means.

6. A circuit breaker having main switch means, an opening spring coupled to said main switch means for moving the same to an open position, first and second toggle link means pivotally connected by a knee pin and coupled to said opening spring, latch means for holding said toggle link means in a rigid substantially straight condition to maintain said opening spring extended and said main switch means closed, the angle between the line of action of said spring and said toggle link means being relatively small, latch release means, an elongate switch closing member movable longitudinally into engagement with said said knee to place said toggle link means in rigid condition, closing spring means urging said closing member toward engagement with said knee pin, cam means rotatably mounted about an axis adjacent said switch closing member, a follower member secured to said closing member and being engageable with said cam means, said cam means having a first portion displaced from said axis for holding said closing member away from said link means and said closing spring means in an extended condition and a second portion proximate to said axis which permits said closing member to engage said knee pin to place said toggle link means in their rigid position, motor means for rotating said cam means to move its second portion into engagement with said follower to release said elongate switch closing member for movement into engagement with said knee pin to initiate a switch closing operation, said motor means also being operable after a switch closing operation to move the first portion of said cam means into engagement with said follower to move the closing member away from said link means and to extend said closing spring means.

7. A circuit breaker having main switch means, opening spring means coupled to said main switch means for moving the same to an open position, first and second toggle link means pivotally connected by a knee pin and coupled to said opening spring means, latch means for holding said toggle link means in a rigid condition to maintain said opening spring means extended and said main switch means closed, latch release means, an elongated switch closing member movable longitudinally into engagement with said knee pin to place said toggle link means in rigid latched condition, closing spring means urging said closing member toward engagement with said knee pin, cam means disposed adjacent said switch closing member and being rotatable about an axis substantially normal to said closing member, said cam means having an involuted surface parallel to said rotational axis, a follower member secured to said closing member and being engageable with said surface, said surface having a first portion displaced from said axis for holding said closing member away from said link means and said closing spring means in an extended condition and a second portion proximate to said axis which permits said closing member to engage said knee pin, motor means for rotating said cam means to move its second portion into engagement with said follower to release said elongate switch closing member for movement into engagement with said knee pin to initiate a switch closing and an opening spring extending operation, said motor means also being operable after a switch closing operation to move the first portion of said surface into engagement with said follower to move the closing member away from said link means and to extend said closing spring means.

8. A repeating circuit interrupter having main switch means, opening spring means coupled to said main switch means for moving the same to an open position, first and second toggle link means pivotally connected by a knee pin and coupled to said opening spring means, latch means for holding said toggle link means in a rigid condition to maintain said opening spring means extended and said main switch means closed, latch release means, an elongate switch closing member movable longitudinally into engagment with said knee pin to place said toggle link means in rigid latched condition, closing spring means urging said closing member toward engagement with said knee pin, cam means disposed adjacent said switch closing member and being rotatable about an axis substantially normal to said closing member, said cam means having an involuted surface parallel to said rotational axis, a follower member secured to said closing member and being engageable with said surface, said surface having a first portion displaced from said axis for holding said closing member away from said link means and said closing spring means in an extended condition and a second portion proximate to said axis which permits said closing member to engage said knee pin, said cam means having an initial position wherein said follower is on said first portion, motor means for rotating said cam means, circuit means for energizing said motor means to move said follower onto said second portion to initiate a switch closing and opening spring extending operation, said circuit means including holding switch means so that said motor is also operable after a switch closing operation to move the first portion of said surface into engagement with said follower to move the closing member away from said link means and to extend said closing spring means, and limit switch means operable to de-energize said motor means when said closing spring is fully extended.

9. A circuit interrupting device having main switch means, opening spring means coupled to said main switch means for urging the same toward an open position, first means engageable with said switch means for holding the same in a closed position and for holding said opening spring means in a charged condition, second means operable to release said switch means from said first means for initiating a switch opening operation, switch closing means operatively associated with said switch means and movable from a first position to a second position to move said switch means into engagement with said first means and into a closed position and to charge said opening spring means, closing spring means urging said closing means toward its second position, electromotive means for normally holding said closing means in its first position and said closing spring means in a charged condition, said electromotive means being operative to release said closing means for movement by said closing spring means to its second position to move said switch means to its closed position and into engagement with said first means and to charge said opening spring means, said electromotive means also being operable after a switch closing operation to move said closing means to its first position and to charge said closing spring means.

10. A circuit interrupting device having main switch means, opening spring means urging said main switch means for movement toward an open position, first means for holding said opening spring means in a charged condition and said main switch means closed, second means operable to release said switch means from said first means for initiating a switch opening operation, switch closing means movable from a first position to a second position for moving said switch means to its closed position and into engagement with said first means and for extending said opening spring means, closing spring means urging said switch closing means toward its second position, electromotive means for normally holding said switch closing means in its first position and said closing spring means in a charged condition, said electromotive means being operative to release said switch closing means for movement by said closing spring means into its second position to move said switch means into its closed position and into engagement with said first means and to charge said opening spring means, said electromotive means also being operable after a switch closing operation to move said switch closing means to its first position and to charge said closing spring means.

11. A circuit interrupting device having main switch means, opening spring means coupled to said main switch means and urging the same for movement to an open position, first means engageable with said switch means to hold the same in a closed position and for holding said opening spring means in a charged condition, second means operable to release said switch means from said first means for initiating a switch opening operation, switch closing means movable from a first position to a second position for moving said switch means into its closed position and into engagement with said first means and for charging said opening spring means, closing spring means urging said closing means toward its second position, cam means for normally holding said switch closing means in its first position and said closing spring means in a charged condition, electromotive means operatively associated with said cam means and operative to release said switch closing means for movement by said closing spring means to its second position to close said main switch means and to charge said opening spring means, said electromotive means also being operable after a switch closing operation to operate said cam means for moving said switch closing means out of its second position and to charge said closing spring means.

References Cited by the Examiner UNITED STATES PATENTS 1,938,408 12/1933 Thumin 200-92 2,156,072 4/1939 Thumin 20092 X 2,794,881 6/1957 Frank 20098 X BERNARD A. GILHEANY, Primary Examiner. 

2. A CIRCUIT BREAKER HAVING MAIN SWITCH MEANS, OPENING SPRING MEANS COUPLED TO SAID MAIN SWITCH MEAND FOR MOVING THE SAME TO AN OPEN POSITON, LINKAGE MEANS COUPLED TO SAID OPENING SPRING MEANS, LATCH MEANS FOR HOLDING SAID LINKAGE MEANS IN A SWITCH CLOSED POSITON AND TO MAINTAIN SAID OPENING SPRING MEANS IN A CHARGED CONDITION, LATCH RELEASE MEANS, A SWITCH CLOSING MEMBER MOVABLE INTO ENGAGEMENT WITH SAID LINKAGE MEANS FOR MOVING THE LATTER TO ITS SWITCH CLOSED POSITION, CLOSING SPRING MEANS URGING SAID CLOSING MEMBER TOWARD ENGAGEMENT WITH SAID LINKAGE MEANS, MOTOR MEANS FOR NORMALLY HOLDING AND CLOSING MEMBER AWAY FROM SAID LINKAGE MEANS AND SAID CLOSING SPRING MEANS IN A CHARGED CONDITION, SAID MOTOR MEANS BEING OPERABLE TO RELEASE SAID CLOSING MEMBER FOR MOVEMENT BY SAID CLOSING SPRING MEANS INTO ENGAGEMENT WITH SAID LINKAGE MEANS TO CLOSE SAID MAIN SWITCH MEANS AND TO CHARGE SAID OPENING SPRING MEANS, SAID MOTOR MEANS ALSO BEING OPERABLE AFTER A SWITCH CLOSING OPERATION TO MOVE SAID CLOSING MEMBER OUT OF ENGAGEMENT WITH SAID LINKAGE MEANS WHEREIN SAID CLOSING SPRING MEANS IN CHARGED. 